when continuing a media set, we first move to the end of the tape and
start with the next (chunk) archive. If that takes long, the task logs
last line is 'moving to end of media' even if we already startet
writing. To make this less confusing, log that we arrived at the
end of the media.
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>